Train Trips Programming Project

CPE 103 Programming Project
Train Trips

Background

It's Friday evening and tomorrow in the early morning hours Jill will have to travel from San Luis Obispo to Sacramento in order to get to the regional programming contest. Since she is afraid of arriving too late and being excluded from the contest she is looking for the train which gets her to Sacramento as early as possible. However, she dislikes waking up too early, so she wants to be able to specify an earliest departure time.

Problem

Jill asks you to help her with her problem. You are given a set of railroad schedules from which you must compute the train with the earliest arrival time that departs on or after Jill's specified departure time. One good thing: Jill is very experienced in changing trains. She can do this instantaneously, i.e., in zero time!!! So if a train arrives in San Jose at 1230 and another train departs San Jose at 1230, Jill can make the connection.

Input

The train schedule is provided in a data file. Sample data file.

Each train trip in the schedule has a unique identifier, a departing location, an arrival location, a departure time and an arrival time.

The identifier and location names are alphanumeric strings containing no blanks. The data fields are delimited by blanks or newlines (the default for a Scanner).

Times are always specified in 4-digit 24-hour time format.

Assumptions:
The data in the schedule is properly formatted.
There are no duplicate trips in the schedule.

Software Design

The core of your solution is a class TrainSchedule that contains two public methods shown below:



public class TrainSchedule

   /** Load a train schedule from the specified InputStream. */
    public void load(java.io.InputStream stream)

   /** Find the best route that satisfies the specified criteria.
    * @param depart the location where the journey begins
    * @param arrive the location where the journey ends.
    * @param startTime the earliest time at which the route may begin.
    * @return String the selected route as a list of trip identifiers separated by blanks,
    *               or "0" if no route meets the specified criteria.
    * @pre depart != arrive
    * @pre depart and arrive exist in the schedule
    * @pre startTime is a valid time 0000 - 2359.
    */
    public String findBestRoute(String depart, String arrive, String startTime)

The remainder of the design is left to the student. Your solution will be graded for the quality of your design. You should create at least one and probably two support classes.
You should use the JGraphT library. If you look carefully in the JGraphT API you can find algorithms that will solve the majority of the problem for you. The instructor's solution is about 150 LOC.
Similarly, you should not write all the time manipulation functions from scratch but take advantage of Java's   Date, Calendar, and SimpleDateFormat classes.

Testing

You must write your own JUnit tests. Here's an example test:

        TrainSchedule sched =
new TrainSchedule();

        String t1 = "A2 SFO FAT 1100
1200\nA1 SFO LAX 1000 1500\nA3 FAT LAX 1201 1400";

        StringBufferInputStream s =
new StringBufferInputStream (t1);

        sched.load(s);

        String result =
sched.findBestRoute("SFO","LAX","0900");       


        assertEquals("A2
A3",result.trim());

Technical note:
Release 0.8.0 and above of JGraphT require Java 1.6 to run. Fortunately we don't need any version 0.8 features, and you can download Release 0.7.3 and it will run on Java 1.5.

Handing in Your Source Electronically

Make sure your name is in the @author tag.
Submit a zip file containing your source code and unit tests to Web-CAT. You do not need to submit the jgrapht.jar file. Web-CAT will use Release 0.7.3.